FAIR VALUE OF FINANCIAL INSTRUMENTS (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2011	Dec. 31, 2010
FAIR VALUE OF FINANCIAL INSTRUMENTS
Estimated fair value of long-term debt	$ 625,202	$ 536,623
Carrying value of the long-term debt	481,632	479,181
Estimated fair value of advances for construction contracts	69,952	75,602
Carrying value of the advances for construction contracts	$ 187,278	$ 186,899

For utilities only, represents the carrying value as of the balance sheet date for payments received by a utility from its customers in advance of performing its obligations under terms of its construction agreements.

No definition available.

+ Details

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- Definition

For utilities only, represents the fair value of the liability as of the balance sheet date for payments received by a utility from its customers in advance of performing its obligations under terms of its construction agreements.

+ References

No definition available.

+ Details

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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- Definition

Sum of the carrying values as of the balance sheet date of all long-term debt, which is debt initially having maturities due after one year from the balance sheet date or beyond the operating cycle, if longer, but excluding the portions thereof scheduled to be repaid within one year (current maturities) or the normal operating cycle, if longer, and after deducting unamortized discount or premiums, if any.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 22

-Article 5

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.5-02.22)

-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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